H.H. Holmes

Dr. H.H. Holmes confessed to 27 murders, and is believed to have killed as many as 200 people, during the time period surrounding the 1893 World's Fair in Chicago. Holmes ran a hotel equipped for killing- outfitted with gas lines into guest rooms, giant furnaces, lime and acid pits, and large vaults- and would torture, suffocate, and strangle his victims before disposing of them in the facility. Holmes was apprehended in Boston in 1894 and died by hanging in Philadelphia in 1896.